(Table T1) In situ methane concentrations of ODP Site 201-1230

A method for quantifying in situ dissolved methane concentrations in sediment cores that have gas voids is described. The method relies on normalizing methane (CH4) in the gas voids to nitrogen (N2) and/or argon (Ar). The principles of the method are presented. The method was tested during Ocean Drilling Program Leg 201, and preliminary results indicate that it can be used to generate reproducible and accurate dissolved methane values if argon and nitrogen are both measured or if one is measured along with pressure of the gas void.本文介绍了一种可定量测定含气体孔隙（gas voids）的沉积岩芯（sediment cores）内原位溶解甲烷（in situ dissolved methane）浓度的方法。该方法以氮气（N₂）和/或氩气（Ar）为参比，对气体孔隙中的甲烷（CH₄）实施归一化定量。本文阐述了该方法的核心原理。该方法已在大洋钻探计划（Ocean Drilling Program）第201航次中开展测试，初步结果表明：若同时测定氩气与氮气含量，或仅测定其中一种气体并结合气体孔隙的压力数据，即可通过本方法获取重现性优异、准确度可靠的溶解甲烷浓度值。